The present disclosure herein relates to a battery module and an electronic device including the same, and more particularly, to management of a secondary battery.
A device using the Internet of Things (IoT), a wearable device, an Energy Storage System (ESS), a Hybrid Electric Vehicle (HEV)/Electric Vehicle (EV), etc. is a system capable of performing a desired function using a battery. Such a battery may be a battery for which only discharge is allowable, but may be a secondary battery that is chargeable and dischargeable in view of efficiency or convenience. The secondary battery may use a single cell, but there are many cases of using a battery module including a plurality of cells connected in series, in parallel, or in series and parallel.
Recently, an electronic device, such as an EV/HEV and an ESS, requiring a high voltage/high capacity energy storage source mainly adopts battery connections in a series and parallel matrix type. For serially connected batteries for a high voltage, since a current between the serially connected batteries is constant and voltages of respective batteries become different due to a difference in internal resistance, cell balancing is required which maintains a voltage between batteries constant in order to prevent the battery life from being lowered. For batteries connected in parallel for high capacity, cell balancing may be performed automatically, but since respective internal resistances of the batteries connected in parallel are different from each other, current values flowing through the batteries become different from each other. Accordingly, for a battery module including secondary batteries connected in parallel, a request is being raised for correcting current values of the respective batteries.